Method and apparatus for controlling the oxygen content of the blood of living animals



Jan. 21, 1947. K|RSCHBAUM 2,414,747

METHOD AND APPAIKATUS FOR CONTROLLING THE OXYGEN CONTENT OF THE BLOOD OFLIVING ANIMALS Filed July 2, 1942 MOTOR INVENTOR. HARRY M..KIRSCHBAUMATTORNEYS Patented Jan. 2!. i941 2,414,747

UNITED sures PATENT OFFICE METHOD AND APPARATUS FOR CONTROL- LING THEOXYGEN CONTENT OF THE BLOOD OF LIVING ANIMALS Harry M. Kirsohbaum.Detroit. Mich. Application July 2, 1942, Serial No. 44am 1 claims. (or.128-142) l The invention relates to means for automatically controllingthe oxygen content or the blood in living animals, being moreparticularly designed i'or use by aviators; but also adapted for 2 duit.C is a control valve and D a conduit leading from the valve to a nosepiece E. or other means for administering the gas to the subject. Theautomatic operating means for the valve use in hospitals and in otherplaces. 5 may be of any suitable construction, either me- It is theobject of the invention to introduce chanical or electrical, which isunder the control oxygen into the lungs of the subject when needed, ormeans sensitive to blood changes. As illusthis being determinedautomatically by the contrated, the valve is periodically opened by atimdition oi his blood. To this end the invention ing mechanism which isactuated by an electric consists in the method and apparatus ashereinmotor whenever the latter is energized. F is a after set forth:motor and G a step-down transmission mecha- In the drawing: nismincluding a rotating crank H provided with Figure 1 is a diagrammaticview of an appaa crank pin I. J is a slidable member for openratus forcarrying out my invention; ing the valve which extends into the path ofthe Figure 2 is an enlarged view of the control pinI so that once ineach revolution of the crank means;

Figure 3 is a section through the control valve; and

through which the oxygen is supplied.

comes darker when it loses its oxygen content. Making use of this, Ihave devised a means of controlling an oxygen administering apparatus bythe color or light absorption capacity of the blood circulating througha, portion of the animal tissue. For instance, in the lobe of the earthere are minute blood vessels or capillarieg through which blood isconstantly circulating. y directare connected to each other by aresilient loop-N ing a beam of light through this tissue the charso thatthey may be clamped against opposite acter of the light will be modifiedby the color sides of the lobe of an ear, 'as indicated at 0. of theblood which'intercepts its path. A light The specific construction ofthe elements L and sensitive electric cell exposed to this beam will Mis not a part of the instant invention. The respond to such changes sothat in connection with element L is, however, of such a character as tosuitable amplifying'and relay means itis adapted be responsive tochanges in the character of light to operate a valve controlling theoxygen supply. falling thereupon. As the source of light is in Theoxygen may be introduced into the lungs of the element M on the oppositeside of the lobe the subject by any suitable means such as a of the ear,it. must be transmitted through said flexible conduit leading to a nosepiece. Thus 40 lobe and thus is aflected by the color or opacity whenthe blood is in normal condition the oxyofthe blood circulating throughthe capillaries. gen supply is cut off, but whenever the blood is Thus achange from the bright red of oxygenated insuflicientlv oxygenated itschange in character blood to the darker bluish color of blood deficientwill automatically bring about an opening of the in oxygen will aflectthe current generation in valve and without any attention on the part ofthe the element L. This current passes through consubject. This rendersit particularly adapted for ductors P to the amplifying means Q, whichalso use by aviators, whose attention is frequently so may be of anysuitable construction, and the amconcentrated on the control 01 themachine as to plifled current actuates arelay switch R; concause them toneglect turning on the oxygen trolling the supply of current to themotor F. supply when needed. The arrangement is such that the switch Ris Various forms of apparatus may be used for carrying out my invention.but as diagrammatically illustrated, A is a conduit leading from asource of oxygen supply. B is a means for regu- Figure 4 is a sectionthrough the nose piece the valve will be opened. This valve, asillustrated, comprises a casing K having an inlet port connected to theconduit Aand an outlet port connected to the conduit D. Within thecasing is a valve seat K located between the inlet and outlet ports, anda valve K connected to a plunger K is normally held to its seat by thetension of a spring K The slide J is connected to the stem K and thuswhenever it is displaced by the pin I, the valve K will be-liited fromits seat to permit flow of oxygen item the conduit A to the conduit D.

The controlling means comprises a light-sensitive cell L andilluminating means M. These open when the blood is in normal conditionand thereby starting the motor F and periodically actuating the valve K.

lating the rate oi now 0! gas through said con 5s The timing oi theactuating mechanism is preterably such as to correspond approximatelywith the breathing cycle of the subject, so that a pulse of oxygen isadmitted with each inhalation of the breath. It is not, however,necessary that the oxygen should be supplied in pulses as the valve mayremain open continuously during the pe-. riod in which oxygen is needed'The advantage of the pulsating operation is that the quantity of oxygensupplied may be more easily regulated.

For convenience in use, the control-means L,

M and the nose piece or nozzle E may be mounted on a head frame S whichholds them in proper relative position. A gauge T may be used inconnection with the amplifying means Q to vis-- ually indicate thecurrent variation due to blood changes.

For use by aviators it may be necessary to adjust the device tocorrespond to individualcharacteristics. Such adjustmentmay be effectedwhile the subject is on the ground and may be used in connection withother testing means for individual responses. When such adjustment ismade the aviator may be assured that it will respond in a similar mannerwhen he is in the air thereby avoiding any danger of lack of oxygen whenit is needed. I

What I claim as my invention is: V

1. In a method of controlling the oxygen contentin the blood of a livinganimal, the steps of modifying a light beam by variations in lightabsorption capacity of a portion of the animal tissue through whichblood is circulating, varying an electrical current by said modifiedlight beam and controlling the introduction of oxygen into the lungs ofthe animalby said variations in current.

of the subject, andmeans for controlling said supply by the current fromsaid cell.

4. An apparatus for automatically controllin the oxygen content in theblood of a living animal comprising a photo-electric cell, a membercontaining a, light source, lmeans for clamping said cell and member onopposite sides "of a portion of the animal tissue in which blood iscirculating, and means for supplying oxygen to the lungs of the animalcontrolled by the current from said cell. 5. An apparatus forautomatically controlling the oxygen content in the blood of a livinganimal subject comprising a photo-electric cell,'a member containing asource of light, means for clamping said cell and member on oppositesides of a portion of the tissue of the subject in which blood iscirculating, means for supplying oxygen to the lungs of the subject, andmeans controlling said supply in itself controlled by saidphoto-electric cell. 7 j

6. An apparatus for-automatically controlling the oxygen content in theblood of a living animal '2. In a method of controlling the oxygen con-I tent in the blood of a living animal, the steps of transmitting lightthrough a portion'of the animal tissue in which'the blood iscirculating, and

directing the transmitted light upon a photoelectric cell whereby thecurrent generated by said cell is varied in accordance withmodifications in the blood due to deficiency in oxygen, and controllingthe introduction. of oxygen into the lungs of the animal by said currentvariations.-

3. An apparatus for automatically controlling subject comprising aphoto-electric cell, a member containing a source of light,-means forclamping said" cell and member on opposite sides of a lobe of an ear ofthe subject whereby the light transmitted through said lobe will bemodified by changes in the blood circulating through said lobe due tooxygen deficiency, an oxygen supply, a conduit leading from said supplyconnecting with the. lungs of the. subject, a valve control-' lingadmission of oxygen from said supply to said conduit, and meanscontrolled by the current generated in said photo-electric cell foroperating said valve.

'7. An apparatus for automatically controlling the oxygen content in'theblood of a living animal subject comprising a photo-electric cell, amember containing a source of light, means for clamping said cell andmember on opposite sides of a lobe of an ear of the subject whereby thelight transmitted through said lobe will be modified the oxygen contentin the blood of a living animal subject, comprising means fortransmitting light through a portion ofv the animal tissue in whichblood is circulating, a photo-electric cell positioned to receive thetransmitted light whereby the current generated by said cell will bevaried in accordance'with modifications in the transmitted light due tomodifications in the blood stream, means for supplying oxygen tothelungs HARRY M. KIRSCHBAUM.

